Scientia Agricultura Sinica ›› 2018, Vol. 51 ›› Issue (5): 855-867.doi: 10.3864/j.issn.0578-1752.2018.05.005

• TILLAGE & CULTIVATION·PHYSIOLOGY & BIOCHEMISTRY·AGRICULTURE INFORMATION TECHNOLOGY • Previous Articles     Next Articles

Remote Sensing Inversion of Leaf Area Index of Winter Wheat Based on Random Forest Algorithm

ZHANG ChunLan1,2,3,4, YANG GuiJun2,3,4, LI HeLi2,3,4, TANG FuQuan1, LIU Chang1,2,3,4, ZHANG LiYan2,3,4   

  1. 1College of Geomatics, Xi'an University of Science and Technology, Xi'an 710054; 2National Engineering Research Center for Information Technology in Agriculture, Beijing 100097; 3Key Laboratory of Agri-informatics, Ministry of Agriculture, Beijing 100097; 4Beijing Engineering Research Center of Agricultural Internet of Things, Beijing 100097
  • Received:2017-07-20 Online:2018-03-01 Published:2018-03-01

Abstract: 【Objective】The objective of this study is to quickly and precisely monitor the growth of winter wheat by inversion of leaf area index (LAI) using random forest algorithm. Thus it could provide a guideline in crop management and mitigation, high and stable yield, agricultural insurance claims, etc.【Method】In this study, field data of canopy reflectance and LAI of winter wheat of four critical growth stages (i.e., jointing period, flag leaf period, flowering period and filling period), were collected under different treatments. The correlation coefficient (r) analysis and the importance analysis of out-of-bag data (OOB) were combined with the random forest algorithm (RF) to determine the more suitable spectral indices and the optimal number of variables for inputs, and then two LAI inversion models (|r| -RF, OOB-RF) were constructed and validated with independent data-sets. Further, the proposed LAI inversion model was applied to the (unmanned aerial vehicle) UAV remote sensing platform to evaluate its performance and reliability for monitoring LAI of winter wheat.【Result】The results showed that the best accuracy of |r|-RF and OOB-RF inversion models was achieved when the top five spectral indices in the correlation and the top two spectral indices in the importance were used as input variables, respectively. The coefficients of determination (R2) of |r|-RF and OOB-RF models during LAI validation were 0.805 and 0.899, and the root mean square errors (RMSE) were 0.431 and 0.307, respectively, which indicated that both |r|-RF and OOB-RF models could well estimate LAI of winter wheat, while the accuracy of the latter was much higher. The retrieved LAI from the UAV hyperspectral images using the OOB-RF model was in well agreement with the ground measured values, with R2=0.761, RMSE=0.320, and the range of estimated values (i.e., 1.02-6.41) also consistent with that actually measured (i.e., 1.29-6.81).【Conclusion】The OOB-RF model constructed in this study not only has high retrieval accuracy, but also can be used to extract high-precision winter wheat LAI information from UAV hyperspectral remote sensing platform.

Key words: unmanned aerial vehicle (UAV), hyperspectral, leaf area index (LAI), random forest algorithm, winter wheat

[1]    贺佳, 刘冰锋, 李军. 不同生育时期冬小麦叶面积指数高光谱遥感监测模型. 农业工程学报, 2014, 30(24): 141-150.
He J, Liu B F, Li J. Monitoring model of leaf area index of winter wheat based on hyperspectral reflectance at different growth stages. Transactions of the Chinese Society of Agricultural Engineering, 2014, 30(24): 141-150. (in Chinese)
[2]    Jin X L, Yang G J, Xu X G, Yang H, Feng H K, Li Z H, Shen J X, Lan Y B, Zhao C C. Combined multi-temporal optical and radar parameters for estimating LAI and biomass in winter wheat using HJ and RADARSAR-2 data. Remote Sensing, 2015, 7(10): 13251-13272.
[3]    Vina A, Gitelson A A, Nguyrobertson A L, Peng Y. Comparison of different vegetation indices for the remote assessment of green leaf area index of crops. Remote Sensing of Environment, 2011, 115(12): 468-3478.
[4]    赵春江. 精准农业研究与实践. 北京: 科学出版社, 2009.     
ZHAO C J. Precision Agriculture Research and Practice. Beijing: Science Press, 2009. (in Chinese)
[5]    王纪华, 赵春江, 黄文江. 农业定量遥感基础与应用. 北京: 科学出版社, 2008.
WANG J H, ZHAO C J, HUANG W J. Basis and Application of Quantitative Remote Sensing of Agriculture. Beijing: Science Press, 2008. (in Chinese )
[6]    宋开山, 张柏, 王宗明, 张渊智, 刘焕军. 基于人工神经网络的大豆叶面积高光谱反演研究. 中国农业科学, 2006, 39(6): 1138-1145.
SONG K S, ZHANG B, WANG Z M, ZHANG Y Z, LIU H J. Soybean LAI estimation with in-situ collected hyperspectral data based on BP-neural networks. Scientia Agricultura Sinica, 2006, 39(6): 1138-1145. (in Chinese)
[7]    GITELSON A A. Wide dynamic range vegetation index for remote quantification of biophysical characteristics of vegetation. Journal of Plant Physiology, 2004, 161(2): 165-173.
[8]    李鑫川, 徐新刚, 鲍艳松, 黄文江, 罗菊花, 董莹莹, 宋晓宇, 王纪华. 基于分段方式选择敏感植被指数的冬小麦叶面积指数遥感反演. 中国农业科学, 2012, 45(17): 3486-3496.
LI X C, XU X G, BAO Y S, HUANG W J, LUO J H, DONG Y Y, SONG X Y, WANG J H. Retrieving LAI of winter wheat based on sensitive vegetation index by the segmentation method. Scientia Agricultura Sinica, 2012, 45(17): 3486-3496. (in Chinese )
[9]    LIANG L, DI L P, ZHANG L P, DENG M X, QIN Z H, ZHAO S H, LIN H. Estimation of crop LAI using hyperspectral vegetation indices and a hybrid inversion method. Remote Sensing of Environment, 2015, 165: 123-134.
[10]   LIU J G, PATTEY E, JEGO G. Assessment of vegetation indices for regional crop green LAI estimation from Landsat images over multiple growing seasons. Remote Sensing of Environment, 2012, 123(3): 347-358.
[11]   夏天, 吴文斌, 周清波, 周勇. 冬小麦叶面积指数高光谱遥感反演方法对比. 农业工程学报, 2013, 29(3): 139-147.
XIA T, WU W B, ZHOU Q B, ZHOU Y. Comparison of two inversion methods for winter wheat leaf area index based on hyperspectral remote sensing. Transactions of the Chinese Society of Agricultural Engineering, 2013, 29(3): 139-147. (in Chinese)
[12]   谢巧云, 黄文江, 梁栋, 彭代亮, 黄林生, 宋晓宇, 张东彦, 杨贵军. 最小二乘支持向量机方法对冬小麦叶面积指数反演的普适性研究.光谱学与光谱分析, 2014, 34(2): 489-493.
XIE Q Y, HUANG W J, LIANG D, PENG D L, HUANG L S, SONG X Y, ZHANG D Y, YANG G J. Research on universality of least squares support vector machine method for estimating leaf area index of winter wheat. Spectroscopy and Spectral Analysis, 2014, 34(2): 489-493. (in Chinese)
[13]   梁栋, 管青松, 黄文江, 黄林生, 杨贵军. 基于支持向量机回归的冬小麦叶面积指数遥感反演. 农业工程学报, 2013, 29(7): 117-123.
LIANG D, GUAN Q S, HUANG W J, HUANG L S, YANG G J. Remote sensing inversion of leaf area index based on support vector machine regression in winter wheat. Transactions of the Chinese Society of Agricultural Engineering, 2013, 29(7): 117-123. (in Chinese)
[14]   韩兆迎, 朱西存, 房贤一, 王卓远, 王凌, 赵庚星, 姜远茂. 基于SVMRF的苹果树冠LAI高光谱估测. 光谱学与光谱分析, 2016, 36(3): 800-805.
HAN Z Y, ZHU X C, FANG X Y, WANG Z Y, WANG L, ZHAO G X, JIANG Y M. Hyperspectral estimation of apple tree canopy LAI based on SVM and RF regression. Spectroscopy and Spectral Analysis, 2016, 36(3): 800-805. (in Chinese)
[15]   李粉玲, 王力, 刘京, 常庆瑞. 基于高分一号卫星数据的冬小麦叶片SPAD值遥感估算. 农业机械学报, 2015, 46(9): 273-281.
LI F L, WANG L, LIU J, CHANG Q R. Remote sensing estimation of SPAD value for wheat leaf based on GF-1 data. Transactions of the Chinese Society for Agricultural Machinery, 2015, 46(9): 273-281. (in Chinese)
[16]   PENUELAS J, ISLA R, FILELLA I, ARAUS J L. Visible and near-infrared reflectance assessment of salinity effects on barley. Crop Science, 1997, 37(1): 198-202.
[17]   HATFIELD J L, KANEMASU E T, ASRAR G, JACKSON R D, PINTER P J, REGINATO R J, IDSO S B. Leaf area estimates from spectral measurements over various planting dates of wheat. International Journal of Remote Sensing, 1985, 6(1): 167-175.
[18]   SHIBAYAMA M T, AKIYAMA T. Seasonal visible, near-infrared and mid-infrared spectra of rice canopies in relation to LAI and above-ground dry phytomass. Remote Sensing of Environment, 1989, 27(2): 119-127.
[19]   RONDEAUX G, STEVEN M, BARET F. Optimization of soil- adjusted vegetation indices. Remote Sensing of Environment, 1996, 55(2): 95-107.
[20]   BARET F, GUVOT G. Potentials and limits of vegetation indices for LAI and APAR assessment. Remote Sensing of Environment, 1991, 35(2): 161-173.
[21]   GITELSON A A, KAUFMAN Y, MERZLYAK M N. Use of green channel in remote of sensing global vegetation from EOS-MODIS. Remote Sensing of Environment, 1996, 58(3): 289-298.
[22]   QI J, CHEHBOUNI A, HUETE A R, KERR Y H, SOROOSHIAN S. A modified soil adjusted vegetation index. Remote Sensing of Environment, 1994, 48(2): 119-126.
[23]   GITELSON A A, MERZLYAK M N. Spectral reflectance changes associated with autumn senescence of Aesculus hippocastanum L. and Acer platanoides L. leaves. Spectral features and relation to chlorophyll estimation. Journal of Plant Physiology, 1994, 143(3): 286-292.
[24]   HABOUDANE D, MILLER J R, PATTEY E, ZARCOTEJADA P J, STRACHAN L B. Hyperspectral vegetation indices and novel algorithms for predicting green LAI of crop canopies: Modeling and validation in the context of precision agriculture. Remote Sensing of Environment, 2004, 90(3): 337-352.
[25]   BROGE N H, LEBLANC E. Comparing prediction power and stability of broadband and hyperspectral vegetation indices for estimation of green leaf area index and canopy chlorophyll density. Remote Sensing of Environment, 2001, 76(2): 156-172.
[26]   HUETE A R, JUSTICE C, LIU H. Development of vegetation and soil indices for MODIS-EOS. Remote Sensing of Environment, 1994, 49(3): 224-234.
[27]   LI F, MISTELE B, HU Y, CHEN X, SCHMIDHALTER U. Comparing hyperspectral index optimization algorithms to estimate aerial N uptake using multi-temporal winter wheat datasets from contrasting climatic and geographic zones in China and Germany. Agricultural and Forest Meteorology, 2013, 180(8): 44-57.
[28]   TANAKA S, KAWAMURA K, MAKI M, MURAMOTO Y, YOSHIDA K, AKIYAMA T. Spectral index for quantifying leaf area index of winter wheat by field hyperspectral measurements: A case study in Gifu prefecture, Central Japan. Remote Sensing, 2015, 7(5): 5329-5346.
[29]   任哲, 陈怀亮, 王连喜, 李颖, 李琪. 利用交叉验证的小麦LAI反演模型研究. 国土资源遥感, 2015, 27(4): 34-40.
REN Z, CHEN H L, WANG L X, LI Y, LI Q. Research on inversion model of wheat LAI using cross-validation. Remote Sensing for Land and Resources, 2015, 27(4): 34-40. (in Chinese)
[30]   LELONG C, BURGER P, JUBELIN G, ROUX B, LABBE S, BARET F. Assessment of unmanned aerial vehicles imagery for quantitative monitoring of wheat crop in small plots. Sensors, 2008, 8(5): 3557-3585.
[31]   POTITHEP S, NAGAI S, NASAHARA K, SUZUKI R. Two separate periods of the LAI-VIs relationships using in situ measurements in a deciduous broadleaf forest. Agricultural and Forest Meteorology, 2013, 169(5): 148-155.
[32]   INOUE Y, GUERIF M, BARET F, SKIDMORE A K, GITELSON A A, SCHLERF M, DARVISHZADEH R, OLIOSO A. Simple and robust methods for remote sensing of canopy chlorophyll content: A comparative analysis of hyperspectral data for different types of vegetation. Plant, Cell and Environment, 2016, 39(3): 2609-2623.
[33]   BREIMAN L. Random forests. Machine Learning, 2001, 45(1): 5-32.
[34]   杨福芹, 冯海宽, 李振海, 高林, 杨贵军, 戴华阳. 基于赤池信息量准则的冬小麦叶面积指数高光谱估测. 农业工程学报, 2016, 32(3): 163-168.
YANG F Q, FENG H K, LI Z H, GAO L, YANG G J, DAI H Y. Hyperspectral estimation of leaf area index for winter wheat based on Akaike’s information criterion. Transactions of the Chinese Society of Agricultural Engineering, 2016, 32(3): 163-168. (in Chinese)
[35]   王丽爱, 马昌, 周旭东, 訾妍, 朱新开, 郭文善.基于随机森林回归算法的小麦叶片SPAD值遥感估算. 农业机械学报, 2015, 46(1): 259-265.
WANG L A, MA C, ZHOU X D, ZI Y, ZHU X K, GUO W S. Estimation of wheat leaf SPAD value using RF algorithmic model and remote sensing data. Transactions of the Chinese Society for Agricultural Machinery, 2015, 46(1): 259-265. (in Chinese)
[36]   GONG P, WANG D X, LIANG S. Inverting a canopy reflectance model using a neural network. International Journal of Remote Sensing, 1999, 20(1): 111-122.
[37]   岳继博, 杨贵军, 冯海宽. 基于随机森林算法的冬小麦生物量遥感估算模型对比. 农业工程学报, 2016, 32(18): 175-182.
YUE J B, YANG G J, FENG H K. Comparative of remote sensing estimation models of winter wheat biomass based on random forest algorithm. Transactions of the Chinese Society of Agricultural Engineering, 2016, 32(18): 175-182. (in Chinese)
[38]   AASEN H, BURKART A, BOLTEN A. Generating 3D hyperspectral information with lightweight UAV snapshot cameras for vegetation monitoring: From camera calibration to quality assurance. ISPRS Journal of Photogrammetry and Remote Sensing, 2015, 108(5): 245-259.
[39]   YUE J B, YANG G J, LI C C, LI Z H, WANG Y J, FENG H K, XU B. Estimation of winter wheat above-ground biomass using unmanned aerial vehicle-based snapshot hyperspectral sensor and crop height improved models. Remote Sensing, 2017, 9(7): 708-727.
[40]   秦占飞, 常庆瑞, 谢宝妮, 申健. 基于无人机高光谱影像的引黄灌区水稻叶片全氮含量估测. 农业工程学报, 2016, 32(23): 77-85.
QIN Z F, CHANG Q R, XIE B N, SHEN J. Rice leaf nitrogen content estimation based on hysperspectral imagery of UAV in Yellow River diversion irrigation district. Transactions of the Chinese Society of Agricultural Engineering, 2016, 32(23): 77-85. (in Chinese)
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